The International journal of prosthodontics最新文献

{"title":"Investigation of Metal-Ceramic Bond Strength in Co-Cr Alloys Produced by Selective Laser Melting at Different Laser Powers.","authors":"Betul Karahasan, Derya Ozdemir Dogan, Nazim Babacan","doi":"10.11607/ijp.9332","DOIUrl":"https://doi.org/10.11607/ijp.9332","url":null,"abstract":"<p><strong>Purpose: </strong>The purpose of this in vitro study was to evaluate the effects of laser power on the relative density, surface roughness, and metal-ceramic bond strength of Co-Cr alloys produced by selective laser melting (SLM), following a single laser track analysis to determine suitable processing parameter window.</p><p><strong>Material and methods: </strong>Single track laser melting was performed at various laser powers and scanning speeds using SLM. Subsequently, three different laser powers (240 W, 300 W, 360 W) were used to produce 12×12×10 mm cube specimens and 25×3×0.5 mm metal strips. The density of the cube specimens (n=5) was determined using the Archimedes method. Microstructural investigations were conducted after metallographic preparation using scanning electron microscope (SEM). Surface roughness of the sandblasted metal strip specimens (n=9) was measured. Ceramic was applied to metal specimens (n=10) in each group, and the strength of the metal-ceramic bond was evaluated through a three-point bend test.</p><p><strong>Results: </strong>SEM analysis showed improved laser track clarity, thickness, and continuity with increasing laser power from 240 W to 360 W. Relative density exceeded 99% for all specimens, with no significant group differences (P=.90). Higher laser power caused keyhole formation and increased surface roughness, peaking at 11.89 ± 3.86 Sa for the P360 group (P<0.01). Specimens produced with the highest laser power demonstrated stronger and more consistent metal-ceramic bond strengths, with significant differences observed between the highest (360 W) and the lowest (240 W) power group (P<.05).</p><p><strong>Conclusion: </strong>While increased laser power enhanced surface roughness and strength of the metal-ceramic bond, it did not lead to substantial changes in the relative density of the specimens.</p>","PeriodicalId":94232,"journal":{"name":"The International journal of prosthodontics","volume":"0 0","pages":"1-19"},"PeriodicalIF":0.0,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144692910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Accuracy Verification of Torque Limiting Devices - A Procedure Using Fundamental Physics.","authors":"Felicitas Hölken, Burak Yilmaz, Monika Bjelopavlovic, Stefan Wentaschek, Samir Abou-Ayash","doi":"10.11607/ijp.9413","DOIUrl":"https://doi.org/10.11607/ijp.9413","url":null,"abstract":"<p><strong>Purpose: </strong>To demonstrate a physics-based technique for testing the accuracy of mechanical torque-limiting devices (MTLDs) and compare it to a digital torque measuring system.</p><p><strong>Materials and methods: </strong>MTLDs from four manufacturers (Camlog, AstraTech, Straumann, NobelBiocare) were selected to assess their accuracy. A manual test setup was developed, each torque measurement was performed three times, and compared to digital torque measurements. Non-parametric statistical tests were used to analyze the results.</p><p><strong>Results: </strong>Torque measurements from the manual and digital techniques did not differ significantly (P < 0.05).</p><p><strong>Conclusion: </strong>The manual technique provided torque measurements similar to those of a commonly used digital system.</p>","PeriodicalId":94232,"journal":{"name":"The International journal of prosthodontics","volume":"0 0","pages":"1-8"},"PeriodicalIF":0.0,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144692903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Effect of Thermocycling and Bleaching on the Color Stability and Lightness of Monolithic CAD-CAM Dental Ceramics.","authors":"Mohammadjavad Shirani, Zahra Naghibeiranvand, Maryam Emami, Kamran Azadbakht","doi":"10.11607/ijp.9429","DOIUrl":"https://doi.org/10.11607/ijp.9429","url":null,"abstract":"<p><strong>Purpose: </strong>The purpose of this in vitro study was to evaluate the effect of coffee thermocycling and carbamide peroxide bleaching on the color stability and lightness of monolithic CAD-CAM ceramics, including zirconia, lithium disilicate (LDS), polymer infiltrated ceramic network (PICN), pre-sintered zirconium-reinforced lithium silicate (PS-ZLS), and PS ZLS with additional sintering (PS-ZLS+AS).</p><p><strong>Materials and methods: </strong>A total of 50 rectangular plate-shaped specimens with A2 shade in 1 mm thickness were investigated (n=10). Each specimen underwent coffee thermocycling for a total of 20 000 cycles and a 20% carbamide peroxide bleaching for 14 days The color changes were calculated using the ΔE00 formula between 3 steps: initially, after thermocycling, and after bleaching steps. A one-way ANOVA, followed by relevant post hoc tests, was used to analyze ΔE00, while a two-way repeated measures ANOVA, followed by Bonferroni-adjusted multiple comparisons for pairwise analyses of lightness, was performed (α = .05).</p><p><strong>Results: </strong>Zirconia and LDS demonstrated the highest stability in color and lightness. In contrast, PS-ZLS and PS-ZLS+AS exhibited significantly greater color changes and lightness reduction during thermocycling, with PS ZLS showing more pronounced alterations than PS-ZLS+AS (P<.001). Bleaching effectively restored the altered color and lost lightness from thermocycling, resulting in less than 1 color change and significantly higher post-bleaching lightness for PICN, PS-ZLS and PS-ZLS+AS.</p><p><strong>Conclusion: </strong>The PS-ZLS groups exhibited the lowest color stability and the greatest lightness reduction during coffee thermocycling. However, additional sintering effectively stabilized the optical properties of PS-ZLS. Bleaching successfully restored the lost lightness and the clinically acceptable original color.</p>","PeriodicalId":94232,"journal":{"name":"The International journal of prosthodontics","volume":"0 0","pages":"1-17"},"PeriodicalIF":0.0,"publicationDate":"2025-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144586027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three Materials for Monolithic Crowns on Zirconia Implants: One-Year Results of a Randomized Clinical Trial.","authors":"Marc Balmer, Miha Pirc, Riccardo D Kraus, Nadja Naenni, Daniel S Thoma, Ronald E Jung","doi":"10.11607/ijp.9455","DOIUrl":"https://doi.org/10.11607/ijp.9455","url":null,"abstract":"<p><strong>Purpose: </strong>to compare the survival rate, the technical, aesthetic, and biological outcomes of three different materials for monolithic crowns on zirconia implants in a randomized clinical trial.</p><p><strong>Materials and methods: </strong>a total of 44 patients were randomly divided into three groups and restored with monolithic implant-supported single crowns: zirconia (Zr), polymer- infiltrated ceramic (PIC), and polymer (P). Follow-up evaluations were conducted after one year. Clinical assessments included survival rates, modified United States Public Health Service (USPHS) scores, White Esthetic Scores (WES), plaque index (PI), bleeding on probing (BoP), and probing depth (PD).</p><p><strong>Results: </strong>After one year, survival rates for monolithic Zr and PIC crowns were 100%, while the P crown group showed a survival rate of 84.6%. At baseline, the PIC crowns achieved the highest USPHS scores; however, this group also showed a noticeable decline over time. The WES remained stable for the Zr but declined significantly for the other groups due to changes in surface texture. PIC exhibited a significant increase in plaque accumulation.</p><p><strong>Conclusions: </strong>Regarding the survival rate, no statistically significant differences were observed between the groups. However, a lower survival rate in the P crown group and superior surface stability in the Zr crowns were noted. Within the limitations of the small sample size and short follow-up period, Zr crowns may be recommended for the restoration of one-piece zirconia implants.</p>","PeriodicalId":94232,"journal":{"name":"The International journal of prosthodontics","volume":"0 0","pages":"1-21"},"PeriodicalIF":0.0,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144532207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Different Concentrations of Nano Hydroxyapatite on the Microshear Bond Strength of Zirconia to Resin Cement.","authors":"Sakineh Nikzad, Azin Zare, Faezeh Atri, Dana Jafarpour, Shahram Zare, Abbas Azari","doi":"10.11607/ijp.9205","DOIUrl":"10.11607/ijp.9205","url":null,"abstract":"<p><strong>Statement of problem: </strong>The impact of varying thicknesses and densities of nano hydroxyapatite (n-HA) coating on the microshear bond strength (μSBS) of zirconia ceramics to resin cements is not well investigated.</p><p><strong>Purpose: </strong>This study aimed to assess the impact of nano hydroxyapatite coating of different concentrations on the microshear bond strength of zirconia ceramics to resin cements.</p><p><strong>Materials and method: </strong>48 Cercon Y-TZP blocks (4×4×4 mm) were randomly divided into 4 groups (n=12); 1) Control group, 2) 5gr n-HA coating, 3) 10gr n-HA coating, and 4) 15gr n-HA coating. The specimens were sintered at 1250°C. The thickness of the coatings was characterized using scanning electron microscopy (SEM). Energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) analyses were carried out to characterize the surface. All specimens were then bonded to Panavia F2.0 cement. Microshear bond testing was carried out using a universal testing machine. Stereomicroscope imaging was used to evaluate the zirconia surface failure mode. The data were analyzed using Kruskall-wallis and Mann-whitney test and P<0.05 was considered statistically significant.</p><p><strong>Results: </strong>The mean μSBS value of the 5gr n-HA coated group with a thickness of 7.71±2.51 micron was 28.30±3.02 Mpa, which was significantly higher than the control group with the mean value of 19.94±1.86 Mpa (P<0.05). The mean μSBS value of the 10gr and 15gr n-HA with thicker coatings were 21.66±3.63 Mpa and 15.23±3.34 Mpa, respectively. Additionally, the main mode of failure for the 5gr n-HA group was a mixed failue. In contrast, the adhesive mode of failure was more dominant in the control group. EDS and XRD analysis revealed the formation of crystalline HA on zirconia blocks, highlighting the predominant zirconia peak at 32°. The SEM analysis of the coated specimens displayed a uniform layer of n-HA coating with evident cracks which were filled with the resin cement. These cracks themselves can help increase the bond strength between ceramic and resin cement.</p><p><strong>Conclusion: </strong>A thin coating of nanocrystalline hydroxyapatite on zirconia surface can be effective in enhancing the micro shear bond strength of these ceramics to resin cements. The microshear bond strength of nHA-coated zirconia significantly improved compared to the untreated specimens.</p>","PeriodicalId":94232,"journal":{"name":"The International journal of prosthodontics","volume":"0 0","pages":"1-21"},"PeriodicalIF":0.0,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144337395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Clinical Validation of an Occlusal Force-based Implant Surgical Guide System: Enhanced Accuracy in Edentulous Patient Treatment with Negligible Positional Deviation.","authors":"Sangjin Suh, Sichan Park, Heechul Kim, Chan Park","doi":"10.11607/ijp.9360","DOIUrl":"10.11607/ijp.9360","url":null,"abstract":"<p><p>A method for designing a 3-piece surgical guide is proposed, which incorporates patient-specific occlusal forces when fabricating digital implant surgical guides for patients with complete edentulism. This approach allows more precise vertical implant placement by incorporating the natural occlusal forces of patients into guide seating. Clinical validation of this system demonstrated improved positional accuracy compared to conventional guided surgery methods, particularly in the critical aspect of vertical positioning. This innovative approach effectively addresses the fundamental challenge of achieving precise implant placement in patients with edentulism, yielding highly predictable surgical outcomes.</p>","PeriodicalId":94232,"journal":{"name":"The International journal of prosthodontics","volume":"0 0","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144337394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of Dentin Bonding and Interfacial Adhesion on the Flexural Properties of a 4 Mol% Yttria Partially Stabilized Zirconia.","authors":"Francesco De Angelis, Matteo Buonvivere, Camilla Mancini, Giuseppe Daniele Rondoni, Mirco Vadini, Camillo D'Arcangelo","doi":"10.11607/ijp.9283","DOIUrl":"10.11607/ijp.9283","url":null,"abstract":"<p><strong>Purpose: </strong>4 mol% yttria partially stabilized zirconia (4Y-PSZ) offers improved translucency compared to 3% tetragonal polycrystalline zirconia but lacks transformation toughening, which may affect its flexural strength. Since adhesive luting was shown to improve mechanical performances of all-ceramic materials, this research evaluated the influence of different cements on the 3-point flexural strength of a 4Y-PSZ bonded to bovine dentin.</p><p><strong>Materials and methods: </strong>Thirty 1-mm-thick dentin slices were obtained from bovine incisors, paired with 1-mm-thick 4Y-PSZ slices, then divided into three groups (n=10) based on the cement investigated: a 10-MDP-free self-adhesive resin cement (SA), a 10-MDP-based adhesive resin cement (MDP-A), and a conventional glass ionomer cement (GI). After luting, the obtained assemblies were cut to obtain 1-mm-wide bar-shaped specimens, which were subjected to 3-point bending test. Fracture loads and flexural strength were recorded, and the modes of failure were analyzed.</p><p><strong>Results: </strong>The highest fracture load and flexural strength were observed in the MDP-A group (76.5 N and 401.5 MPa), followed by the SA group (62.3 N and 326.8 MPa). The GI group exhibited the lowest values (45.6 N and 239.5 MPa). In MDPA group samples predominantly exhibited concurrent dentin and zirconia fractures without debonding, while in SA and GI groups a frequent incidence of debonding at the interface was observed.</p><p><strong>Conclusion: </strong>Adhesive cementation enhances the flexural strength of 4Y-PSZ bonded to bovine dentin, with the 10-MDP-based resin cement yielding the best performances. Effective adhesive techniques could improve the mechanical performance of 4Y-PSZ restorations, making them more reliable for clinical applications.</p>","PeriodicalId":94232,"journal":{"name":"The International journal of prosthodontics","volume":"0 0","pages":"1-21"},"PeriodicalIF":0.0,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144337398","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"INfORM/IADR Key Points for Good Clinical TMD Practice - A Critical Comment.","authors":"Jens Christoph Türp, Güzin Neda Hasanoğlu Erbaşar","doi":"10.11607/ijp.9336","DOIUrl":"10.11607/ijp.9336","url":null,"abstract":"<p><strong>Purpose: </strong>To critically evaluate the recently published INfORM/IADR consensus paper containing ten key points for good clinical practice in the management of patients with temporomandibular disorders.</p><p><strong>Materials and methods: </strong>After perusing the text of the document, followed by intensive discussion, the 10 key points were carefully analyzed and commented.</p><p><strong>Results: </strong>Two key points could be replaced by other (clinically relevant) statements. In addition to terminologically and semantically imprecise formulations some verbal descriptions remain superficial and vague. While no distinction was made between acute and chronic TMDs, the INfORM/IADR author group differentiates between first-line and second-line therapeutic modalities without explaining the rationale for such a classification. Furthermore, no medication recommendations were made.</p><p><strong>Conclusions: </strong>We anticipate that the INfORM/IADR publication will have a beneficial impact on the care of TMD patients. However, in our opinion, a reflection on some of the contents of the 10-point document seems justified in order to reduce the risk of misinterpretation of some statements, which could lead to inappropriate diagnostic and therapeutic measures.</p>","PeriodicalId":94232,"journal":{"name":"The International journal of prosthodontics","volume":"0 0","pages":"1-15"},"PeriodicalIF":0.0,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144337399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stress Distribution on Mucosa Soft Tissue of Alveolar Ridge at the Dislocation of BPS: A Three-Dimensional Finite Element Analysis.","authors":"Sheng Fang, Kailun Chen, Xiaohan Lin, Zhu Tie, Ziqin Lin, Junjie Lin, Rui He, Botao Wang","doi":"10.11607/ijp.9312","DOIUrl":"10.11607/ijp.9312","url":null,"abstract":"<p><strong>Purpose: </strong>To analyze the stress distribution and displacement of alveolar ridge mucosal tissue when Biofunctional prosthetic system (BPS) dentures were dislocated under three conditions.</p><p><strong>Materials and methods: </strong>CBCT was used to obtain the data of the patient's jaw, and the patient's BPS scan data was gained through the oral scanner. Through Mimics, Geomagic Studio and Unigraphics NX software, the CT data files were built into 3D finite element models (FEM) of the upper and lower edentulous jaws, mucosa and BPS complete dentures, then analyze the stress distribution and mucosal tissue displacement caused by ridge mucosal tissue when BPS dentures were dislocated under three conditions (BPS denture dislocation along the anterior alveolar ridge, BPS denture dislocation caused by the left posterior teeth biting hard food or anterior teeth biting hard food), respectively.</p><p><strong>Results: </strong>In general, under the three different circumstances, the value in the relatively large area of the maxillary and mandibular equivalent stress was similar, but the deformation value of the mandibular mucosa was significantly higher than that of the maxillary mucosa.</p><p><strong>Conclusion: </strong>When BPS complete denture is dislocated, the stress distribution of the mucosa under the base of the maxillary and mandibular dentures is uniform and extensive, and the stress distribution of the palatal mucosa is small. In comparison to the dislocation of BPS dentures that were removed and worn independently, the mucosal stress distribution was more uneven when BPS dentures were subjected to biting hard food, resulting in greater deformation.</p>","PeriodicalId":94232,"journal":{"name":"The International journal of prosthodontics","volume":"0 0","pages":"1-19"},"PeriodicalIF":0.0,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144337400","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Post-Curing Duration on Color Changes in 3D-Printed Fixed Polymeric Restorations of Varying Thicknesses.","authors":"Ho-Jin Lee, Seok-Hwan Cho, Chonghwa Kim, Hang-Nga Mai, Thaw Thaw Win, Shilpa Rana, Du-Hyeong Lee","doi":"10.11607/ijp.8982","DOIUrl":"10.11607/ijp.8982","url":null,"abstract":"<p><strong>Purpose: </strong>This study aimed to evaluate color changes in 3D-printed acrylic restorations of varying thicknesses and exposed to different post-curing durations.</p><p><strong>Materials and methods: </strong>Three virtual full-contour maxillary central incisor crowns with different buccal thicknesses (1.0, 1.5, and 2.0 mm) were designed and manufactured using a 3D printer and a photopolymer (n = 9 per thickness group). The lightness, hue, and chroma of the restorations were measured at baseline (prior to post-curing) and again at 5 min intervals up to 30 min during the post-curing process using a spectrophotometer. Color changes (ΔE) were calculated by comparing the CIE L*, a*, b* coordinates at different time points to the baseline values. Repeated-measures analysis of variance and the Tukey's post-hoc test were used for statistical analysis (α = .05).</p><p><strong>Results: </strong>The ΔE increased significantly within the first 5 min of post-curing and was more gradual thereafter in all thickness groups. The ΔE values were significantly higher in the 1.5 and 2.0 mm thickness groups compared to the 1.0 mm thickness group. The C* coordinate was seen to increase significantly within the first 5 min of post-curing, and did not change significantly afterward.</p><p><strong>Conclusions: </strong>During post-curing, the hue of a 3D printed polymeric restoration changed to yellowish and reddish shades, the brightness decreased, and the saturation increased. Most color changes occurred within the first 5 min of post-curing and were also more noticeable in thicker restorations.</p>","PeriodicalId":94232,"journal":{"name":"The International journal of prosthodontics","volume":"0 0","pages":"1-18"},"PeriodicalIF":0.0,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144337396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}